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On properties of mass transfer in an Algol-type binary system:an example of VV Vir

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Research in Astronomy and Astrophysics 2014年第2期14卷 179-192页

作者： Jia Zhang sheng-Bang Qian Lin-qiao Jiang Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

Some properties of mass transfer within a semi-detached binary system are discussed based on an example of VV Vir. The observations and analysis of VV Vir show that it is a semi-detached binary system with the less massive cooler component filling its Roche lobe, which is also called an Algol-type binary system. Based on the parameters of this semi-detached binary, a theoretical study on the mass flow is carded out, including the trajectory of the mass flow, the position, radius and temperature of the impact spot caused by the mass flow, the inconsistent form of the mass flow and the possibly huge rate of energy transfer carried by the mass flow. Humps and distortions in light curves of VV Vir are deemed to be weak evidence for the theoretical results.

关键词： binaries eclipsing -- stars individual (VV Vir) -- techniques photo-metric

SDSS J012119.10 001949.9:a very short period M dwarf contact binary from SDSS stripe 82

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Research in Astronomy and Astrophysics 2015年第12期15卷 2237-2243页

作者： Lin-qiao Jiang sheng-Bang Qian Jia Zhang Yunnan Observatories Chinese Academy of Sciences Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of Sciences University of Chinese Academy of Sciences

We present the first multicolor photometric observations of the short period low-mass eclipsing binary SDSS J012119.10-4301949.9. By using the 2013 version of the Wilson-Devinney code, the photometric solutions are derived. It is found that the system is in a contact configuration （f = 18.9± 6.0%） with a moderate mass ratio of 0.5 ± 0.01. A third light contributing about 6.1± 1.3% of the total luminosity in the V band was found, which may come from a cool tertiary component. The derived high orbital inclination （i - 83.9°± 0.5°） and the almost symmetric three light curves suggest that the determined parameters are reliable. Both the color class and spectral class of the system correspond to a spectral type of M0, which may indicate that SDSS J012119.10-001949.9 belongs to a very rare class of M dwarf contact binaries that are below the theoretical short period limit.

关键词： binaries: eclipsing -- stars: individual (SDSS J012119.10-001949.9) --techniques: photometric

Relationship of atmospheric boundary layer depth with thermodynamic processes at the land surface in arid regions of China

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Science China Earth Sciences 2011年第10期54卷 1586-1594页

作者： ZHANG Qiang ZHANG Jie qiao Juan WANG sheng Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province Key Open Laboratory of Arid Climate Change and Disaster Reduction Lanzhou Institute of Arid Meteorology China Meteorological Administration Lanzhou 730020 China Key Laboratory of Meteorological Disasters (KLMD) Ministry of Education Nanjing Information Engineering University Nanjing 210044 China Meteorological Bureau of Xi' an City Xi'an 710016 China Institute of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

The atmospheric boundary layer （ABL） is an important physical characteristic of the Earth＇s atmosphere. Compared with the typical ABL, the ABL in arid regions has distinct features and is formed by particular mechanisms. In this paper, the depth of the diurnal and nocturnal ABLs and their related thermodynamic features of land surface processes, including net radiation, the ground-air temperature difference and sensible heat flux, under typical summer and winter conditions are discussed on the basis of comprehensive observations of the ABL and thermodynamic processes at the land surface carried out in the extreme arid zone of Dunhuang. The relationships of the ABL depth in the development and maintenance stages with these thermodynamic features are also investigated. The results show that the depth of the ABL is closely correlated with the thermodynamic features in both development and maintenance stages and more energy is consumed in the development stage. Further analysis indicates that wind velocity also affects ABL development, especially the development of a stable boundary layer in winter. Taken together, the analysis results indicate that extremely strong thermodynamic processes at the land surface are the main driving factor for the formation of a deep ABL in an arid region.

关键词： arid region deep atmospheric boundary layer development and maintenance thermodynamic process at the land surface main driving factor

基于Revit二次开发实现快速铺砖的插件及应用

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广州建筑 2024年第5期52卷 90-94页

作者：陈乐乔升访陈航广州市建筑科学研究院集团有限公司广州510440 广州建筑股份有限公司广州510030

为解决人工手动绘制铺砖方案低下的问题,本文基于Revit2022软件,采用C#语言编码,编码过程中通过调用RevitAPI文档,融入扫描线算法,使用VistualStudio2022编译平台编译代码,进行软件打包安装,研发出自动布置铺砖生成功能插件。在Revit中... 详细信息

为解决人工手动绘制铺砖方案低下的问题,本文基于Revit2022软件,采用C#语言编码,编码过程中通过调用RevitAPI文档,融入扫描线算法,使用VistualStudio2022编译平台编译代码,进行软件打包安装,研发出自动布置铺砖生成功能插件。在Revit中实现了给出边界条件便自动给出自动铺砖解决方案,快速完成装饰深化模型中的铺砖。并开发了自动编码参数赋值功能,实现了每块瓷砖唯一的编码赋值;开发的数据导出功能打通了Revit软件与Excel数据的连接,消除了BIM模型数据孤岛,将明细工单信息流转至Excel。应用表明Revit二次开发的自动铺砖功能生成工字铺、井字铺、错缝铺铺砖方案,在10000m2的地板上生成铺装方案最快1s内完成,速度快、效果更好。铺砖方案信息制成工单显著提升设计师工作效率的同时,也助力减少后期施工返工,指导采购节约材料,有效发挥出BIM模型的信息价值。研究成果可为BIM模型在深化设计比选方案、施工阶段落地应用上提供新思路。

关键词： Revit二次开发扫描线算法铺砖数据导出

POLYMERIZATION AND CHARACTERIZATION OF HIGH CONDUCTIVITY AND GOOD ADHENSION POLYPYRROLE FILMS FOR ELECTROMAGNETIC INTERFERENCE SHIELDING

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Chinese Journal of Polymer Science 2010年第6期28卷 923-930页

作者： Yong-sheng qiao La-zhen Shen Tao Dou Ming Hu Institute of Special Chemicals Taiyuan University of Technology Taiyuan 030024 China School of Chemistry and Chemical Engineering Shanxi Datong University Datong 037009 China School of Electronic Information Engineering Tianjin University Tianjin 300072 China

Polypyrrole（PPy） shows a favorable application in the electromagnetic interference（EMI） shielding due to its good electrical conductivity and outstanding air *** PPy films with high conductivity and good adhesion were successfully polymerized on the surface of insulating epoxy resin substrates using chemical *** factors affecting the properties of PPy films,such as the surface morphology,adhesion between PPy film and substrate,electrical conductivity,EMI shielding effectiveness（SE）,were *** adhesion was improved significantly through a three-step surface pretreatment of epoxy resin substrates including removing impurities,roughening,and surface modification with silane coupling *** enhancement in the conductivity of PPy films of about one order of magnitude was achieved by adding dopant in FeCl_3 *** higher the conductivity,the better the shielding *** sodium p-toluenesulfonate doped PPy film as example,EMI SE was in the practically useful range of about 30 dB over a wide frequency range from 30 MHz to 1500 *** PPy film samples were characterized by scanning electron microscopy （SEM）,infrared spectra（IR）,X-ray photoelectron spectroscopy（XPS） and the flange coaxial transmission *** fourpoint probe method was used to measure conductivity of PPy films.

关键词： Polypyrrole film EMI Conductivity Adhesion

23种常用中成药治疗失眠的临床研究证据图分析

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中国中药杂志 2024年第14期49卷 3952-3962页

作者：马永庆邢畅李巧凤徐征张金生吴承玉南京中医药大学中医学院江苏南京210023 郑州大学第五附属医院福华街院区中医康复科河南郑州450052 河南中医药大学第三附属医院脑病科河南郑州450008

运用证据图系统检索和梳理中成药治疗失眠的临床研究证据,了解该领域证据分布特点,发现中成药治疗失眠相关研究存在的问题。检索3个国家药物目录中明确提及治疗失眠的中成药,检索建库至2023年8月的中、英文文献。采用图、表展示结果。... 详细信息

运用证据图系统检索和梳理中成药治疗失眠的临床研究证据,了解该领域证据分布特点,发现中成药治疗失眠相关研究存在的问题。检索3个国家药物目录中明确提及治疗失眠的中成药,检索建库至2023年8月的中、英文文献。采用图、表展示结果。最终纳入中成药23种,相关文献299篇,包括随机对照试验(RCTs)236篇,非随机对照试验(non-RCTs)35篇,回顾性研究7篇,系统评价/Meta分析17篇,指南和专家建议或共识4篇。文献占比较大的是百乐眠胶囊、乌灵胶囊、养血清脑颗粒;结局指标包括睡眠评定量表、临床有效率、安全性指标、焦虑抑郁评分等。结果表明,中成药治疗失眠研究整体呈增长趋势,但研究证据相对较少,研究以单中心、小样本和短周期为主;临床定位宽泛,中医优势不足;结局指标对生活质量、随访及复发率方面关注度不够;RCT整体偏倚风险偏高,系统评价/Meta分析整体质量较低,回顾性研究总体评分不高,non-RCT均未提及随访时间、失访率及样本量估算,结果可信度降低。建议以中医药临床研究规范来设计治疗失眠的中成药研究方案,将中医证候积分评价作为重要结局指标,多关注患者生活质量、随访及复发情况,提高有效治疗失眠中成药的可及性和经济性,加强医保政策与中成药政策的衔接,合理提升具有明确疗效和安全证据支持的中成药在医保甲类目录中的占比。

关键词：失眠中成药干预性研究系统评价/Meta分析回顾性研究证据图经济性

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基于全景展开图像的隧道围岩节理识别方法

长江科学院院报 2024年第5期41卷 116-123页

作者：方星桦阳军生黄定詹双桥张聪中南大学土木工程学院长沙410075 中南林业科技大学土木工程学院长沙410004 广西交通设计集团有限公司南宁530012 湖南省水利水电勘测设计规划研究总院有限公司长沙410007

为了解决目前节理信息识别方法仅适用于局部岩体图像的问题,采用全景展开图像方法,将采集到的局部洞壁围岩图像进行特征点提取、点云模型重建、矫正拼接处理,获得高分辨率的隧道洞壁围岩全景展开图像。通过图像预处理、小尺寸特征图片的... 详细信息

为了解决目前节理信息识别方法仅适用于局部岩体图像的问题,采用全景展开图像方法,将采集到的局部洞壁围岩图像进行特征点提取、点云模型重建、矫正拼接处理,获得高分辨率的隧道洞壁围岩全景展开图像。通过图像预处理、小尺寸特征图片的smaAt-Unet神经网络识别、小尺寸图片识别结果的融合拼接,对洞壁围岩全景展开图像的节理信息进行了区域粗略分割识别。采用Zhang-Suen算法和8邻域连通域分析方法,从骨架化与骨架线分离、毛刺剔除、骨架线连接方面进行了算法分析计算,完成了节理信息的细化提取。对体积节理数和节理空间产状信息进行了量化分析,最终建立了一种基于全景展开图像的隧道洞壁围岩节理信息识别方法。工程应用结果表明,洞壁围岩全景展开图像识别后,节理面空间方程的平均拟合误差为0.90,说明该识别方法能够较好地识别全景展开图像中的节理信息。另外,洞壁围岩图像采集具有时间短、易操作、灵活性较高的优点,对现场施工影响较小,该识别方法能够较为快速地完成节理信息识别,给现场施工与动态设计提供参考。

关键词：隧道洞壁围岩全景展开图像 smaAt-Unet神经网络节理识别

The research on floe ice force acting on the"Xue Long"icebreaker based on synthetic ice test and virtual mass numerical method

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Journal of Hydrodynamics 2021年第2期33卷 271-281页

作者： Wei Guo qiao-sheng Zhao Yu-kui Tian Wan-chao Zhang State Key Laboratory of Hydrodynamics China Ship Scientific Research CenterWuxi 214082China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

When the ice-going ships advance in the polar region,the navigation in the floe ice region is often encountered,the hull will suffer the high-frequency contact force produced by the floe ice,which will affect the navigation performance of the ***,it is necessary to predict the water and ice force acting on the hull *** this paper,the numerical simulation and experimental verification will be conducted for the polar scientific research ship-"Xue Long".Based on the computational fluid dynamics(CFD)and DEM theory,a virtual mass method is proposed to realize the predicting of the water and ice force and the simulation of the interaction phenomenon between the ice and hull,the numerical method is built to calculate the force acting on the *** the same time,the synthetic ice is used to carry out the experimental research on the advancing straight with different speeds and the oblique navigation with different drift *** optimal virtual mass coefficient is determined through the comparison and analysis of the numerical simulation and test results under typical *** to the optimal virtual mass coefficient,the numerical simulation is carried out with different speeds and drift angles,which is compared with the experiment more *** is found that the virtual mass method based on the combination of CFD and DEM can simulate the overturning and the sliding along the hull of the floe ice vividly,the relative error of the total resistance between model test and numerical method in advancing straight is almost within 10%,while the relative error of the total longitudinal force in oblique navigation is almost within 15%.

关键词： "Xue Long"ship synthetic ice model test computational fluid dynamics(CFD) DEM virtual mass method drift angle

Optimal design of APD biasing circuit

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Optoelectronics Letters 2007年第3期3卷 237-240页

作者： SUN Chun-sheng QIN Shi-qiao WANG Xing-shu ZHU Dong-hua College of Optoelectronic Science and Technology National University of Defense Technology Changsha 410073 China Department of Weaponry Engineering Naval University of Engineering Wuhan 430033 China

This paper proposes a control method for avalanche photodiode(APD) reverse bias with temperature compensation and load resistance compensation. The influence of background light and load resistance on APD detection circuit is analyzed in detail. A theoretical model of temperature compensation and load resistance compensation is established,which is used for APD biasing circuit designing. It is predicted that this control method is especially suitable for LD laser range finder used on vehicles. Experimental results confirm that the design proposed in this paper can considerablely improve the performance of range finder.

关键词：雪崩二极管偏流电路优化设计温度补偿负载电阻补偿